This invention relates to a disc brake and more particularly, to a floating caliper-type disc brake of the type in which the disc receives braking forces on the opposite surfaces and in which a braking force acting on one surface of the disc is received by one end portion of a support and a braking force acting on the other surface of the disc is received by the other end portion of the support whereby the force applied to the support is evenly distributed to thereby reduce the amount of material of the support without sacrificing the rigidity of the support.
There have been proposed and practically employed a variety of floating caliper-type disc brakes and in one typical one of such prior art disc brakes, a braking force acting on one surface of the disc is directly transmitted to the support and a braking force applied to the other surface of the disc is indirectly transmitted to the support through the housing and slide bolts or slide pins to be ultimately transmitted to a vehicle to thereby attain the intended object. In such a prior art disc brake, since it is designed that the substantial portion of braking force provided by a pair of friction pads is to be received by one end portion of the support, there is the disadvantage that the support should be strong enough to bear such substantial braking force resulting in increase in size.
Furthermore, in a prior art disc brake for a two-wheeled vehicle and especially, for the front wheel of a vehicle, since the support of the disc brake is secured to the boss on the front forks, the mounting holes in the support by means of which the support is secured to the boss are not symmetric with respect to the two arms of the support.
In the disc brake having the left-hand arm of its support secured to the body of a vehicle as shown in FIG. 4, for example, when the brake is applied, the moment produced by the brake pads is greater on the support right-hand arm than on the support left-hand arm. Therefore, it has been generally practiced that the support arm receiving a greater moment is reinforced by making it thicker and larger than the support arm receiving a smaller moment. However, this method increases the weight of the brake itself and requires extra material and has been found to be an unsatisfactory solution.